>> The latest Cook's Illustrated addresses that practice.  In a
>> nutshell:

>> Apparently if you put enough water* into the dough to roll it
>> out easily, it baked up tough, too much gluten was forming.
>> They needed a way to tenderize the finished crust without
>> reducing the amount of water.

>> *8 tablespoons

>> The article said the many recipes say that a teaspoon of
>> vinegar or lemon juice (in other words, acid) can tenderize
>> the dough, claiming the gluten formation is inhibited at lower
>> pH values.  However, their science editor says that isn't
>> true until the pH drops below 5.  Accomplishing that led to
>> an incredibly sour crust.

>> So what they needed was something that is not water but is
>> still wet, to replace some of the water.  Answer: Vodka.
>> 4 tablespoons each water and vodka.

> Vodka is acid?